The Baltimore Longitudinal Study of Aging (BLSA), the Intramural NIA's major research program on human aging, has been conducted at the Gerontology Research Center since 1958. The study continues to represent a consortium of scientists who work to characterize normal and pathological aging. The BLSA consists of a series of longitudinal and cross-sectional studies oriented toward characterizing the human aging processes. The scientific goals include identifying age associated differences among individuals and changes in individuals over time; to characterize transitions from normal to pathological aging; to determine the relative contribution of aging, disease processes, cohort effects and secular effects; to expand the scientific understanding of predictors and risk factors for specific diseases and other end points and where possible to explore mechanisms for normal and/or pathological changes. The Acting Clinical Director is the current Director, BLSA; Longitudinal Studies Scetion (LSS) and clinical support staff administer and manage the BLSA operations and the clinical evaluations of the research volunteers. LSS scientists also conduct research with the BLSA. The BLSA Executive Committee, an internally comprised committee of GRC scientists and the Director, BLSA, is responsible for oversight of BLSA operations and research directions. The total BLSA population as of 9/1/01 includes 1505 participants (762 women; 743 men), 568 inactive (273 women; 295 men), and 898 deceased (137 women; 761 men). At present, 23% of all active men and 31% of the active women are African-American. Overall, over 30% of the active participants are members of a minority group. Between 10/1/99 and 9/11/00, 462 participants visited the GRC for the regular 2 to 2-1/2-day visit. This includes 99 new participants. A high priority is systematic follow-up. Re-enrollment efforts directed at inactive participants, and attrition prevention strategies targeting currently active participants are being actively persued. Sarah Holmes, Ph.D., Project Director for follow-up, continues in charge of this aspect of the program. The transportation program for non-local participants implemented this year has been successful and cost effective. Of the 898 deceased participants, we have death certificates on file for 88%, physician and/or hospital reports for 39%, and autopsy reports for 20%.